Effective extraction of information on time-varying user interest

ABSTRACT

An apparatus sets, for a user, a time-width indicating a period of time which precedes a current time and for which a usage history of the user is to be acquired, and extracts an interesting matter of the user from the usage history acquired within the set time-width. The apparatus provides help information obtained based on the extracted interesting matter to the user to acquire a result of an operation that is performed by the user in response to provision of the help information, where the time-width for the user is set based on the acquired result of the operation by the user.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority of theprior Japanese Patent Application No. 2017-139098, filed on Jul. 18,2017, the entire contents of which are incorporated herein by reference.

FIELD

The embodiments discussed herein are related to effective extraction ofinformation on time-varying user interest.

BACKGROUND

Systems have hitherto been proposed in which the characters of users(personas) are analyzed from histories of the users and informationmatched with the users is extracted and provided.

As technologies in related art to analyze the characters of users, forexample, a message apparatus is known in which analysis of thecharacters of persons in a certain user group who uses the messageserver, which is based on character-of-person data, is instructed andthe result of the analysis of the characters of the persons is displayed(refer to Japanese Laid-open Patent Publication No. 2006-338581). Inaddition, an advertisement distribution method is known in which usageinformation is collected from household electrical appliances of users,users who are supposed to buy goods are extracted based on the collectedusage information, and advertisement is transmitted to the extractedusers (refer to International Publication Pamphlet No. WO2014/64940).

SUMMARY

According to an aspect of the invention, an apparatus sets, for a user,a time-width indicating a period of time which precedes a current timeand for which a usage history of the user is to be acquired, andextracts an interesting matter of the user from the usage historyacquired within the set time-width. The apparatus provides helpinformation obtained based on the extracted interesting matter to theuser to acquire a result of an operation that is performed by the userin response to provision of the help information, where the time-widthfor the user is set based on the acquired result of the operation by theuser.

The object and advantages of the invention will be realized and attainedby means of the elements and combinations particularly pointed out inthe claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and arenot restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating an exemplary configuration of aninformation extraction apparatus according to an embodiment;

FIG. 2 is a diagram for describing an example of how to calculate aninterest group probability;

FIG. 3 is a diagram for describing another example of how to calculatethe interest group probability;

FIG. 4 is a flowchart illustrating an exemplary process to set a timewidth;

FIG. 5 is a flowchart illustrating an exemplary process to output a helpin accordance with an interest;

FIG. 6 is an explanatory diagram exemplifying the transition ofinterests and time widths;

FIG. 7 is an explanatory diagram for describing an exemplary helpoutput;

FIG. 8 is an explanatory diagram for describing another exemplary helpoutput; and

FIG. 9 is a block diagram illustrating an exemplary hardwareconfiguration of the information extraction apparatus according to theembodiment.

DESCRIPTION OF EMBODIMENTS

Each user has multiple interesting matters and the matter which the userhas the greatest concern is varied with time. For example, the matterwhich the user has the greatest concern in a mediate to long termhistory may not coincide with the matter which the user has the greatestconcern in a shorter term history.

Accordingly, a difference may arise between the interesting mattersanalyzed in the technologies in the related art and the currentinteresting matters of the user. As a result, there is a problem in thatthe accuracy of information to be provided to the user may be decreasedin the technologies in the related art.

In one aspect, the present disclosure provides an information extractionapparatus, an information extraction program, and an informationextraction method capable of accurately extracting interesting mattersof a user.

An information extraction apparatus, an information extraction program,and an information extraction method according to embodiments willherein be described with reference to the drawings. The same referencenumerals are used to identify the components having the same functionsin the embodiments. A duplicated description of such components isomitted herein. The information extraction apparatus, the informationextraction program, and the information extraction method describedbelow in the embodiments are only examples and are not intended to limitthe embodiments. The embodiments described below may be appropriatelycombined within a consistent range.

FIG. 1 is a block diagram illustrating an exemplary configuration of aninformation extraction apparatus according to an embodiment. Aninformation extraction apparatus 1 illustrated in FIG. 1 is, forexample, an information processing apparatus, such as a personalcomputer (PC). Referring to FIG. 1, the information extraction apparatus1 includes a similar user determining unit 101, a time width settingunit 102, an interest extracting unit 103, and an information providingunit 104.

The information extraction apparatus 1 refers to a usage log 2 in whicha usage history of each user is recorded to extract an interestingmatter of each user in the usage history. The information extractionapparatus 1 provides information based on the extracted interestingmatter to the user by displaying the information on a screen. Theinformation to be provided to the user includes help information matchedwith the interesting matter in a help system of a tool and recommendedinformation for recommending an item matched with the interestingmatter. The user is capable of acquiring a variety of informationmatched with his/her interest in the above manner.

The usage log 2 is a log file in which the usage history (including thecontent of operations and the operation dates and times) of varioustools is stored, for example, for each user identifier (ID), whichidentifies each user. In other words, the usage log 2 is an example ofthe usage history of the user.

The various tools the usage histories of which are stored in the usagelog 2 include, for example, a Web browser and a business application.For example, in the case of the Web browser, the content of operationsincluding Web sites accessed with the Web browser and the content ofsearch in search sites is stored in the usage log 2 along with theoperation dates and times. In the case of the business application, thecontent of operations including search and selection of items in thebusiness application, confirmation of the content, and re-selection ofan item that was selected is stored in the usage log 2 along with theoperation dates and times.

The similar user determining unit 101 compares the usage histories ofthe respective users in the usage log 2 with each other to determinewhether each user has the usage history similar to that of a targetuser. For example, the similar user determining unit 101 compares theusage history of the target user in the usage log 2 with the usagehistory of another user therein to acquire the degree of similaritybetween the usage histories. Then, the similar user determining unit 101determines the user the calculated degree of similarity of whom ishigher than or equal to a predetermined threshold value to be a similaruser. The similar user determining unit 101 supplies the result of thedetermination to the time width setting unit 102.

The time width setting unit 102 sets a time width from the current time,within which the usage history of the target user is acquired from theusage log 2. The time-width indicates a period of time which precedes acurrent time and for which a usage history of each user is to beacquired. The time width setting unit 102 acquires the usage historywithin the set time width from the current time, based on informationabout the dates and times in the usage history, from the usage historyof the target user stored in the usage log 2. The time width settingunit 102 supplies the acquired usage history of the target user to theinterest extracting unit 103.

The interest extracting unit 103 extracts interesting matters of theuser in the usage history, based on the usage history of the user, whichis acquired from the usage log 2 within the time width set by the timewidth setting unit 102. For example, the interest extracting unit 103calculates an interest group probability indicating the degree ofinterest of the user, for each of multiple predetermined interestingmatters, based on the usage history of the user acquired from the usagelog 2. Then, the interest extracting unit 103 extracts the interestingmatter the interest group probability of which is higher than or equalto a predetermined threshold value in the decrement order of thecalculated interest group probabilities. Then, the interest extractingunit 103 supplies the extracted interesting matters to the informationproviding unit 104.

How to calculate the interest group probability will now be described indetail with reference to FIG. 2 and FIG. 3. FIG. 2 and FIG. 3 areexplanatory diagrams for describing examples of calculation of theinterest group probability. For example, FIG. 2 is a diagram fordescribing an example of how to calculate the interest group probabilityfor an interesting matter having an interest name of “Get replacement”.FIG. 3 is a diagram for describing an example of how to calculate theinterest group probability for an interesting matter having an interestname of “Reuse part”.

As illustrated in FIG. 2, actions (the content of operations) supposedto be performed by the user having an interesting matter and thecredibility of each action for the interesting matter are set in advancefor the interesting matter, such as “Get replacement”.

For example, in the case of “Get replacement”, an operation to searchfor a part (“FC_SEARCH”) and an operation to select a past part(“KAKOBUMON”) are supposed to be the actions to be performed by the userhaving the interesting matter “Get replacement”. Accordingly, theactions, such as “FC_SEARCH”, “KAKOBUMON”, “PCOM_VIEW”, and “PNTC_VIEW”,which are supposed to be performed by the user having the interestingmatter, are set in advance for the interesting matter “Get replacement”.

In addition, different actions have different degrees of trust for theinteresting matter. For example, in the case of “Get replacement”, theoperation to select a past part (“KAKOBUMON”) has a probability of beingperformed higher than that of the operation to search for a part(“FC_SEARCH”). In other words, “KAKOBUMON” has a credibility higher thanthat of “FC_SEARCH”. The value of the credibility indicating the degreeof trust is set in advance for each action so that the different degreesof trust are reflected.

In the calculation of the interest group probability of “Getreplacement”, the interest extracting unit 103 counts the number of theactions of each action that is set in advance for the interest matter“Get replacement”, based on the usage history of the user acquired fromthe usage log 2. Then, the interest extracting unit 103 multiplies thecalculated number of the actions by the value of the credibility that isset in advance to calculate a calculation value (the number ofactions*credibility) of each action. Then, the interest extracting unit103 divides the sum of the calculation values (Σ(the number ofactions*credibility) by the log size (the number of cases) acquired fromthe usage log 2 to calculate the interest group probability as theprobability of the user having the interesting matter “Get replacement”.

Similarly, as illustrated in FIG. 3, in the case of “Reuse part”, forexample, the operation to search for a part (“FC_SEARCH”) and anoperation to confirm a past part (“WL_OPEN”) are supposed to be theactions to be performed by the user having the interesting matter “Reusepart”. Accordingly, these actions and the value of the credibilityindicating the degree of trust of each action are set in advance for theinteresting matter “Reuse part”.

In the calculation of the interest group probability of “Reuse part”,the interest extracting unit 103 counts the number of the actions ofeach action that is set in advance for the interest matter “Reuse part”,based on the usage history of the user acquired from the usage log 2.Then, the interest extracting unit 103 multiplies the calculated numberof the actions by the value of the credibility that is set in advance tocalculate a calculation value (the number of actions*credibility) ofeach action. Then, the interest extracting unit 103 divides the sum ofthe calculation values (Σ(the number of actions*credibility) by the logsize (the number of cases) acquired from the usage log 2 to calculatethe interest group probability as the probability of the user having theinteresting matter “Reuse part”. As described above, the interestextracting unit 103 calculates the interest group probability for eachof the multiple interesting matters and extracts the interesting matterbased on the calculated interest group probability.

The information providing unit 104 provides information based on theinteresting matter extracted by the interest extracting unit 103 to theuser. The information is provided to the user through screen displayusing a display unit (not illustrated) such as a display or audio outputusing an audio output unit (not illustrated). For example, theinformation providing unit 104 is a help system that provides helpinformation about a tool (such as a business application) matched withthe interesting matter of the user or a recommendation system thatpresents a recommended item matched with the interesting matter of theuser. The information providing unit 104 provides the information, suchas the help information or the recommended item, matched with theinteresting matter of the user to the user with reference to a databasein which the pieces of information to be provided in association withthe interesting matters are stored in advance.

In addition, the information providing unit 104 acquires a result of anoperation which is performed by the user via an input unit (notillustrated), such as a keyboard or a mouse, in response to theprovision of the information based on the interesting matter extractedby the interest extracting unit 103 to the user. For example, theinformation providing unit 104 acquires an operation to close a windowon which the provided information is displayed or a click operation toconfirm the provided information. Then, the information providing unit104 records the result of the operation by the user, which is acquiredin response to the provision of the information based on the extractedinteresting matter, as a result of confirmation of the providedinformation.

The time width setting unit 102 sets a time width (a time span) used forthe acquisition of the usage history from the usage log 2, based on theresult of confirmation recorded by the information providing unit 104,that is, the result of the operation by the user, which is acquired inresponse to the provision of the information based on the interestingmatter extracted by the interest extracting unit 103 to the user.

For example, when the information provided to the user by theinformation providing unit 104 is information useful for the user, thatis, when appropriate information provision is performed, the result ofan expected operation, such as the click operation to confirm theprovided information, may be acquired. For example, the result of anoperation expected to have the effect of help may be acquired inresponse to the provision of the help information in the help system. Incontrast, when appropriate information provision is not performed, forexample, the operation to close the window on which the providedinformation is displayed is performed and the result of an expectedoperation, such as the click operation to confirm the providedinformation, is not acquired.

Accordingly, when the result of an expected operation is acquired, thereis a small difference between the interesting matter extracted based onthe usage history acquired from the usage log 2 within the set timewidth and the interesting matter which the user actually has, and it isestimated that appropriate information provision is performed based onthe interesting matter. Accordingly, when the result of an expectedoperation is acquired, the time width setting unit 102 keeps the timewidth that is set.

In contrast, when the result of an expected operation is not acquired,there is a large difference between the interesting matter extractedbased on the usage history acquired from the usage log 2 within the settime width and the interesting matter which the user actually has, andit is estimated that appropriate information provision is not performed.Accordingly, when the result of an expected operation is not acquired,the time width setting unit 102 adjusts the time width that is set toanother time width.

More specifically, the time width setting unit 102 sets time widths thatare sequentially increased from an initial value, and determines whetherthe interesting matter that is extracted with the current time widthbeing set is different from the interesting matter that is extractedwith the previous time width being set. Then, for a different time widthfor which the extracted interesting matter is made different, the timewidth setting unit 102 determines whether the result of an operationthat is performed by the user in response to the information provisionbased on the different interesting matter meets a predeterminedcondition. When the result of an operation by the user meets thepredetermined condition, for example, when the result of an operation bythe user is the click operation to confirm the provided information, thetime width setting unit 102 sets the different time width as a timewidth that will be subsequently used.

The setting of a time width in the time width setting unit 102 will nowbe described. FIG. 4 is a flowchart illustrating an exemplary process toset the time width. Referring to FIG. 4, upon start of the process, inStep S1, the information extraction apparatus 1 acquires data about thetarget user with reference to the usage log 2. In Step S2, the similaruser determining unit 101 compares the usage histories of the respectiveusers in the usage log 2 with each other to determine whether the usagehistory of the target user is similar to that of another user.

When the usage history of the target user is similar to that of anotheruser (YES in Step S2), the process goes to Step S3. In Step S3, the timewidth setting unit 102 refers to a time width table T1 in which the timewidth set for each user is stored to make the time width of the targetuser equal to that of the similar user determined to be similar to thetarget user in the usage history.

When the usage history of the target user is not similar to that ofanother user (NO in Step S2), the process goes to Step S4. In Step S4,the time width setting unit 102 initializes the time width from thecurrent time to the initial value that is set in advance.

In Step S5, the interest extracting unit 103 extracts the interest (theinteresting matter) by using the time width set in Step S3 or S4 as thecurrent time width. Step S5 to S11 will be repeatedly performed at apredetermined time interval (for example, every one day).

In Step S6, the time width setting unit 102 determines whether it is notthe beginning of the process and the interest (the interesting matter)is the same as the interest (the interesting matter) extracted in theprevious loop. For example, when the order of arrangement is the same asthat of the extracted multiple interesting matters, the time widthsetting unit 102 determines that the extracted interest is the same asthe interest extracted in the previous loop. When multiple differentinteresting matters are extracted or the order of arrangement isdifferent from that of the extracted multiple interesting matters, thetime width setting unit 102 determines that the extracted interest isdifferent from the interest extracted in the previous loop.

When the interest (the interesting matter) is the same as the interest(the interesting matter) extracted in the previous loop (YES in StepS6), the process goes to Step S10. When the interest (the interestingmatter) is different from the interest (the interesting matter)extracted in the previous loop (NO in Step S6), the process goes to StepS7. In Step S7, the time width setting unit 102 acquires the effect ofhelp (the result of confirmation recorded by the information providingunit 104).

In Step S8, the time width setting unit 102 determines whether the userhas performed an expected action (operation) for the provision of help(information provision) for any of the extracted interests (interestingmatters), based on the acquired result of confirmation. For example,when the user has performed an expected operation, such as the clickoperation to confirm the provided information, the time width settingunit 102 makes affirmative determination. The time width setting unit102 otherwise makes negative determination.

When the user has performed an expected operation (YES in Step S8), theprocess goes to Step S9. In Step S9, the time width setting unit 102sets, in the time width table T1, the time width in the current loop asthe time width of the target user. Then, the process illustrated in FIG.4 is terminated.

When the user has not performed an expected operation (NO in Step S8),the process goes to Step S10. In Step S10, the time width setting unit102 increments the time width (the time width in the currentloop+predetermined value (α)). In Step S11, the time width setting unit102 determines whether the incremented time width is greater than orequal to a predetermined maximum value (the time width≥the maximumvalue). When the time width is not greater than or equal to thepredetermined maximum value (NO in Set S11), the process goes back toStep S5. When the time width is greater than or equal to thepredetermined maximum value (YES in Set S11), the process illustrated inFIG. 4 is terminated.

A process to output a help in accordance with an interest will now bedescribed in detail as an example of the information provision to theuser. FIG. 5 is a flowchart illustrating an exemplary process to outputa help in accordance with an interest.

Referring to FIG. 5, upon start of the process, in Step S20, theinterest extracting unit 103 acquires the usage log 2 within the timewidth set by the time width setting unit 102 for the target user.

In Step S21, the interest extracting unit 103 calculates an interestgroup probability for each of the multiple predetermined interestingmatters (an interest A, an interest B, an interest C, . . . ), based onthe acquired usage log 2. The interest extracting unit 103 stores theinterest group probability for each of the calculated multipleinteresting matters, in an interest table T2. Here, the interest groupprobability indicates a degree of interest of each of the interestingmatters for a user.

In Step S22, the information providing unit 104 converts the interestgroup probability of each of the multiple interesting matters into ahelp output ratio of each interesting matter with reference to theinterest table T2. For example, the information providing unit 104converts the interest group probability of each interesting matter,considering the total interest group probability of the extractedinterest matters as 100%. For example, when the interests A and B areextracted, the interest A is 34%, and the interest B is 10%, the ratioof the interest A is 34/(34+10)=77.2% and the ratio of the interest B is10/(34+10)=22.7%.

In Step S23, the information providing unit 104 outputs a help matchedwith the help output ratio of each interesting matter to provideinformation to the user. For example, when the ratio of the interest Ais 77% and the ratio of the interest B is 23%, the information providingunit 104 provides pieces of help information to the user having theinterest A at the ratio of 77%. In addition, the information providingunit 104 provides pieces of help information to the user having theinterest B at the ratio of 23%.

In Step S24, the information providing unit 104 acquires the result ofthe operation performed in response to the provision of the informationbased on the interesting matter to the user, and records (stores) theresult of the operation as an effect (the result of confirmation) in aconfirmation result table T3. For example, when the information aboutthe interest A is provided, the information providing unit 104 recordsthe result of confirmation for each confirmation method of the interestA in the confirmation result table T3.

In Step S25, the information providing unit 104 acquires a logical OR ofthe results of confirmation of items in the confirmation result tableT3. In Step S26, the information providing unit 104 outputs the acquireddata to the time width setting unit 102 as the result of confirmationrecorded by the information providing unit 104.

FIG. 6 is an explanatory diagram exemplifying the transition ofinterests and time widths. Graphs G1 and G2 in the diagram in FIG. 6illustrate estimated degrees of interest in different interestingmatters of a user. The right ends of the graphs G1 and G2 indicate thecurrent time. The interest of the graph G2 is higher than the interestof the graph G1 at the current time.

If the usage history is acquired from the usage log 2 within a timewidth H1, as illustrated in FIG. 6, a long period during which the graphG1 is higher than the graph G2 is included in the time width H1.Accordingly, the information (for example, a help) based on the graph G1is provided to the user.

FIG. 7 is an explanatory diagram for describing an exemplary helpoutput. For example, as illustrated in FIG. 7, a help screen 201 basedon the graph G1 is displayed for a user 300 in a display unit 200.However, the user 300 has an interest of the graph G2 higher than thatof the graph G1 at the current time. Accordingly, the user 300recognizes that the help screen 201 is not matched with his/herinterest. In such a case, the user 300 does not perform, for example,the click operation to confirm the help screen 201 and performs anotheroperation. Accordingly, the information extraction apparatus 1 sets atime width H2 longer than the time width H1 in the next loop.

When the usage history is acquired from the usage log 2 within the timewidth H2, the graph G2 is higher than the graph G1 for a period longerthan the period during which the graph G1 is higher than the graph G2.Accordingly, the information (for example, a help) based on the graph G2is provided to the user.

FIG. 8 is an explanatory diagram for describing another exemplary helpoutput. For example, as illustrated in FIG. 8, the help screen 201 basedon the graph G2 is displayed for the user 300 in the display unit 200.This help screen 201 is matched with the interest of the user 300 at thecurrent time. In such a case, the user 300 performs an expectedoperation, such as the click operation to confirm the help screen 201.Accordingly, the information extraction apparatus 1 sets the time widthH2 as the time width that will be subsequently used and is capable ofproviding the information matched with the interest of the user 300.

As described above, the information extraction apparatus 1 includes thetime width setting unit 102 that sets the time width from the currenttime, which is used for the acquisition of the usage history of the userfrom the usage log 2. The information extraction apparatus 1 alsoincludes the interest extracting unit 103 that extracts the interestingmatter of the user in the usage history, based on the usage historyacquired from the usage log 2 within the set time width. The informationextraction apparatus 1 further includes the information providing unit104 that provides information based on the extracted interesting matterto the user and acquires the result of an operation performed by theuser in response to the information provision. The time width settingunit 102 sets the time width used for the acquisition of the usagehistory, based on the result of an operation by the user, acquired bythe information providing unit 104. Since the information extractionapparatus 1 sets the time width used for the acquisition of the usagehistory, based on the result of an operation that is performed by theuser in response to the information provision based on the extractedinteresting matter, as described above, the information extractionapparatus 1 is capable of accurately extracting the interesting matterof the user, based on the acquired usage history.

The time width setting unit 102 sets a time width longer than theprevious time width and determines whether the interesting matter thatis extracted with the current time width being set is different from theinteresting matter that is extracted with the previous time width beingset. If the interesting matter that is extracted with the current timewidth being set is different from the interesting matter that isextracted with the previous time width being set and the result of anoperation performed by the user in response to the information provisionbased on the different interesting matters meets a predeterminedcondition, the time width setting unit 102 sets the current time widthas a time width that will be subsequently used. Accordingly, since theinformation extraction apparatus 1 sets a time width by evaluating theresult of an operation, which is performed by the user in response tothe information provision based on the different interesting matters,when the interesting matter extracted with the current time width ismade different from the interesting matter extracted with the previoustime width while setting the time widths to be sequentially increased,the information extraction apparatus 1 is capable of more accuratelyextracting the interesting matter of the user.

The information extraction apparatus 1 further includes the similar userdetermining unit 101, which determines the users having similar usagehistories in the usage log 2. The time width setting unit 102 sets, fora target user for which the time width is to be set, the time width ofthe user the usage history of whom is determined to be similar to theusage history of the target user, based on the time width table T1. Theinformation extraction apparatus 1 is capable of extracting theinteresting matter under a condition matched with the users havingsimilar usage histories by setting the time width matched with the usershaving similar usage histories in the above manner.

The interest extracting unit 103 extracts the degree of interest (theinterest group probability) of each of the multiple interesting mattersof the user, based on the usage history extracted from the usage log 2within the set time width. The information providing unit 104 providesthe information based on the interest group probabilities of themultiple interesting matters. Accordingly, the information extractionapparatus 1 is capable of providing the information matched with thedegree of interest of each of the multiple interesting matters of theuser.

The components in the respective blocks illustrated in the drawings arenot necessarily physically configured in the manner illustrated in thedrawings. In other words, specific aspects of dispersion and integrationof the respective blocks are not limited to the ones illustrated in thedrawings and all or part of them may be functionally or physicallydispersed or integrated in arbitrary units depending on various loadsand the usage conditions.

All or part of the various processing functions performed in theinformation extraction apparatus 1 may be performed on a centralprocessing unit (CPU) (or a microcomputer, such as a micro processingunit (MPU) or a micro controller unit (MCU)). All or part of the variousprocessing functions may be performed on programs analyzed and executedon the CPU (or the microcomputer, such as the MPU or MCU) or hardwareusing wired logic. The various processing functions in the informationextraction apparatus 1 may be performed through cooperation of multiplecomputers using cloud computing.

The various processes described in the above embodiments may be realizedby executing programs that are prepared in advance in the computer. Anexample of the computer (hardware) executing the programs havingfunctions similar to those in the above embodiments will now bedescribed. FIG. 9 is a block diagram illustrating an exemplary hardwareconfiguration of the information extraction apparatus 1 according to theembodiment.

Referring to FIG. 9, the information extraction apparatus 1 includes aCPU 11, a read only memory (ROM) 12, a random access memory (RAM) 13,and a storage unit 14. The information extraction apparatus 1 alsoincludes a display 15, an interface (I/F) 16, a keyboard 17, a mouse 18,a scanner 19, and a printer 20. The components (11 to 20) in theinformation extraction apparatus 1 are coupled to each other via a bus21.

The CPU 11 is an arithmetic processing unit that controls the entireinformation extraction apparatus 1. The ROM 12 is a non-volatile memorythat stores programs of the information extraction apparatus 1. The RAM13 is a volatile memory used as a working memory in the arithmeticprocessing performed by the CPU 11. The storage unit 14 is, for example,a hard disk drive (HDD) and stores an information extraction program 14a and a variety of information. The variety of information stored in thestorage unit 14 may include the usage log 2 described above.

The display 15 is a device that displays data, such as a document, animage, and/or functional information, concerning the result ofprocessing. The display 15 displays, for example, a cursor, icons, or atool box. For example, a thin film transistor (TFT) liquid crystaldisplay, a plasma display, or an organic electroluminescent (EL) displaymay be used as the display 15.

The interface 16 interfaces between an network 22 and the inside of theinformation extraction apparatus 1 and controls input and output of datainto and from an external apparatus. For example, the interface 16 iscoupled to, for example, a local area network (LAN), a wide area network(WAN), or the Internet, which serves as the network 22, via acommunication line and is coupled to another apparatus over the network22. For example, a modem or a LAN adaptor may be used as the interface16.

The functional components described above with reference to FIG. 1 arecapable of being realized by the CPU 11 that executes the informationextraction program 14 a stored in the storage unit 14.

The information extraction program 14 a may not be stored in the storageunit 14. For example, each program may be stored in a flexible disk tobe loaded in the information extraction apparatus 1, that is, in a“portable physical medium”, such as a floppy disk (FD), a compact discread only memory (CD-ROM), a digital versatile disc (DVD) disk, amagneto-optical disk, or an integrated circuit (IC) card. Then, theinformation extraction apparatus 1 may acquire each program from theportable physical medium for execution. Alternatively, each program maybe stored in another computer or a server apparatus coupled to theinformation extraction apparatus 1 over the network 22, such as a publicswitched network, the Internet, a LAN, or a WAN, and the informationextraction apparatus 1 may acquire each program for execution.

All examples and conditional language recited herein are intended forpedagogical purposes to aid the reader in understanding the inventionand the concepts contributed by the inventor to furthering the art, andare to be construed as being without limitation to such specificallyrecited examples and conditions, nor does the organization of suchexamples in the specification relate to a showing of the superiority andinferiority of the invention. Although the embodiments of the presentinvention have been described in detail, it should be understood thatthe various changes, substitutions, and alterations could be made heretowithout departing from the spirit and scope of the invention.

What is claimed is:
 1. An information extraction apparatus comprising: amemory; and a processor coupled to the memory and configured to: set,for a first user among users, a first time-width as a time-widthindicating a period of time which precedes a current time and for whicha usage history of each of the users is to be acquired, extract a firstinteresting matter of the first user from the usage history acquiredwithin the set first time-width, and provide help information obtainedbased on the extracted first interesting matter to the first user toacquire a result of an operation that is performed by the first user inresponse to provision of the help information, wherein the processorsets the first time-width for the first user, based on the acquiredresult of the operation by the first user.
 2. The information extractionapparatus of claim 1, wherein the processor is configured to: in a statewhere the first time-width is set for the first user, set, for the firstuser, a second time-width longer than the first time-width, and set thesecond time-width as a time-width for which the usage history of thefirst user is to be subsequently acquired, when a second interestingmatter extracted within the second time-width is different from thefirst interest matter extracted within the first time-width and a resultof the operation performed by the first user in response to provision ofthe help information obtained based on the second interesting mattermeets a predetermined condition.
 3. The information extraction apparatusof claim 1, wherein the processor is configured to: determine, for thefirst user, a second user among the users whose usage history is similarto the usage history of the first user, and set, for the first user, asecond time-width set for the second user, based on setting informationon time-widths set for the respective users.
 4. The informationextraction apparatus of claim 1, wherein the processor is configured to:calculate, based on the usage history, a degree of interest of each of aplurality of interesting matters for the first user, and provide, as thehelp information, information obtained based on the degree of interestof each interesting matter to the first user.
 5. A non-transitory,computer-readable recording medium having stored therein a program forcausing a computer to execute a process comprising: setting, for a firstuser among users, a first time-width as a time-width indicating a periodof time which precedes a current time and for which a usage history ofeach of the users is to be acquired; extracting a first interestingmatter of the first user from the usage history acquired within the setfirst time-width; and providing help information obtained based on theextracted first interesting matter to the first user to acquire a resultof an operation that is performed by the first user in response toprovision of the help information, wherein the first time-width for thefirst user is set based on the acquired result of the operation by thefirst user.
 6. The non-transitory, computer-readable recording medium ofclaim 5, the process further comprising: in a state where the firsttime-width is set for the first user, setting, for the first user, asecond time-width longer than the first time-width; and setting thesecond time-width as a time-width for which the usage history of thefirst user is to be subsequently acquired, when a second interestingmatter extracted within the second time-width is different from thefirst interest matter extracted within the first time-width and a resultof the operation performed by the first user in response to provision ofthe help information obtained based on the second interesting mattermeets a predetermined condition.
 7. The non-transitory,computer-readable recording medium of claim 5, the process furthercomprising: determining, for the first user, a second user among theusers whose usage history is similar to the usage history of the firstuser; and setting, for the first user, a second time-width set for thesecond user, based on setting information on time-widths set for therespective users.
 8. The non-transitory, computer-readable recordingmedium of claim 5, the process further comprising: calculating, based onthe usage history, a degree of interest of each of a plurality ofinteresting matters for the first user; and providing, as the helpinformation, information obtained based on the degree of interest ofeach interesting matter to the first user.
 9. A method comprising:setting, for a first user among users, a first time-width as atime-width indicating a period of time which precedes a current time andfor which a usage history of each of the users is to be acquired;extracting a first interesting matter of the first user from the usagehistory acquired within the set first time-width; and providing helpinformation obtained based on the extracted first interesting matter tothe first user to acquire a result of an operation that is performed bythe first user in response to provision of the help information, whereinthe first time-width for the first user is set based on the acquiredresult of the operation by the first user.
 10. The method of claim 9,further comprising: in a state where the first time-width is set for thefirst user, setting, for the first user, a second time-width longer thanthe first time-width; and setting the second time-width as a time-widthfor which the usage history of the first user is to be subsequentlyacquired, when a second interesting matter extracted within the secondtime-width is different from the first interest matter extracted withinthe first time-width and a result of the operation performed by thefirst user in response to provision of the help information obtainedbased on the second interesting matter meets a predetermined condition.11. The method of claim 9, further comprising: determining, for thefirst user, a second user among the users whose usage history is similarto the usage history of the first user; and setting, for the first user,a second time-width set for the second user, based on settinginformation on time-widths set for the respective users.
 12. The methodof claim 9, further comprising: calculating, based on the usage history,a degree of interest of each of a plurality of interesting matters forthe first user; and providing, as the help information, informationobtained based on the degree of interest of each interesting matter tothe first user.